Drilling apparatus.



No. 800,702. PATENTBD OCT. 3, 1905. J. F. WILLARD. DRILLING APPARATUS.

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WITNESSES:

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[NI/ENTOR 1 W0? (WM ATTORNEY No. 800,702. PATENTED OCT. 3, 1905 J. F. WILLARD.

DRILLING APPARATUS.

APPLICATION FILED MAR.21, 1904.

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DRILLING APPARATUS.

Specification of Letters Patent.

Patented Oct. 3, 1905.

Application filed March 21, 1904- Serial No. 199,119-

To all w/wm it may concern:

Be it known that I, JACOB F. WILLARD, a citizen of the United States, residing at Colo rado City, in the county of El Paso and State of Colorado, have invented a new and useful Improvementin Drilling Apparatus, of which the following is a specification.

My invention relates to an improvement in impact rock-drills in which a uniform stroke is assured and the drill-shaft automatically rotated and automatically fed.

The peculiar improvements in this invention will appear throughout the description and claims. 7

In the accompanying drawings, Figure 1 is a top plan view of the interior arrangement of the drill mechanism. Fig. 2 is across-sectional view taken on the line a a in Fig. 1. Fig. 3 is a horizontal sectional view taken on the line a (a, but showing the construction near one end of the drill-casing. Fig. 4 is a view of the contact-block and release-bumper. Fig. 5 is a perspective of the outside of the drill ready for attaching to power. illustrates the movementof the rotating mechanism.

In the several figures the same parts are indicated by the same characters.

Referring to the details of construction, 1 is the casing of the drill and is to be constructed of suitable metal in a shape similar to that shown in Fig. 5. 2 is the removable top of the said casing.

3 is a double crank-shaft bearing atpoints 4 and r and intended to transmit the power from the connecting-handle or flexible shaft to the pitmen 5 and 6 and ultimately to the various parts of the mechanism. The pitmen are fastened in a suitable manner, preferably by the pivoted fastenings 8 and 8, as shown, to the driver-head 7 which driver-head carries the clutching and turning mechanism.

9 is an ordinary polygonal bar of steel which when sharpened at one end, as shown, becomes a rock-drill and drill-shaft.

9 is a circular opening through the block 10 in which the drill-shaft operates and in which. it may be moved freely.

10 is a spring-actuated contact-block, hav ing a square top and slanting sides acting as a wedge. Against the square top of the blocks bears the coil-spring 26.

11 and 15 are clutch pawls or dogs, having over their top ends curved plate metal springs, (shown as 12 and 16,) which normally bearlightl y against the plug 10. These clutch- Fig. 6'

pawls are pivoted in the circular base 18, which is securely and permanently fastened to the tappet-plate'17. The base 18 and the tappet-plate 17 are placed in a circular opening in the driver-head 7 in such a manner as to hold them securely in place, but to permit of their ready rotation. As the driverhead 7 is retracted by the pitmen the clutchpawls are brought firmly in contact with the contact-block 10. The springs-12 and 16 are by reason of theresistance of the spring 26 forced to lie fiat against the inner surfaces of the contact-block and the clutch-pawls. As the clutch-,pawls recede and come into contact with the blocklO their upper parts are pressed from each other'andthe lower points closed in on the drill and grip it firmly. The driverhead and clutch-pawls continuing to recede the drill-shaft is carried along with it and the spring 26 compressed. When the cranks in the crank-shaft reach the opposite position to that shown in Fig. 1 and begin to describe the last half of the semicircle described by them, the crank and crank-shaft is to be released, and .the spring 26 will throw the driver head, tappet plate, drill shaft, and other attached parts rapidly to the end of stroke and until the force of the spring is almost expended. When the end of the stroke is reached, the release-bumper 14 strikes the end of the casing 1 and by means of the rods 13 and 13, connecting it with the block 10, causes the pressure of the block on the clutchpawls to be instantly decreased if the same has not already occurred sufliciently to allow the momentum of the drill to carry it forward against the rock to be drilled, permitting automatic feed of drill and shaft.

The driver-head 7 is guided by the guides 20 and 21, attached to the sides of the casing.

It will be seen that the drill is almost released when the end of the forward stroke is reached; but it is not entirely released because of the springs 12 and 16, which resume their normal position and compel the clutch-pawls to retain a moderate grasp on the drill-shaft. If it were not for this, it would be possible for the drill to rebound before the action of the crank-shaft withdrew the release-bumper from the end of the casing and allowed the clutch-pawls to secure a new hold.

The other important feature of this device which remains to be described is the part thereof which serves to revolve the drill-shaft a fraction of a revolution between the strokes as it is retracted. This part consists of the tappet wheel or plate 17, which has projecting from its rim the spokes 19. These spokes in conjunction with the pivotal spring-cleats serve to revolve the drill. During the downward portion of the strokes two of the spokes pass along on opposite sides of the cleats 23 and 24 until the end of the stroke is almost reached, at which time one of the spokes passes off the cleat 24. The cleat 24 being released is instantly moved outward by the action of the spiral spring 27 and instead of allowing the spoke to return on the upward movement in the same direction the cleat comes in contact with it and causes it to move obliquely and between the two cleats 23 and 24. In Fig. 6 the broken line extending from Z top indicates the course of one of the spokes during the downward stroke. At an on the upward stroke the spoke is engaged by the clcat 524i and is moved to a, thence continues its course to 0. When the end of the upward motion is reached, there is a repetition of the movement described, and a sufficient number of strokes varying according to the number of spokes on the tappet-wheel will be required to make a complete revolution of the drill-shaft and drill. The spring 27 is held in place by contact with a shoulder projecting from the inner side of the casing.

Thus far in this specification I have referred to the conditions and directions as they would exist while a drill was being operated in a downward direction. The drill, however, may be used in any position and. to drill a hole in any direction. Should the drill be operated in any position in which the attraction of gravity would cause the drill-shaft if loose to fall away from the object to be drilled in, the constant pressureof the spring 26, or when the pressure of that spring is expended then by the springs 12 and 16, would cause the clutch-pawls to retain suflicient grasp to prevent any such rebound or backward movement. It will also be seen that the impact is caused entirely by the momentum of the drill, as it is almost entirely released at the end of the stroke. The impact of the drill-shaft is entirely sufficient for drilling.

The power by which this drill is operated and the manner of applying the power is not a part of this invention; but it is preferable to use some sort of a ratchet attachment to connect with the crank-shaft which will allow the drill-shaft to take a downward movement without impediment. It might be operated by an ordinary crank attached to the handle on the shaft; but this would not be entirely satisfactory, as the motion would be very irregular and jerky.

I am aware of the fact that drilling appliances have been invented with tappet-plates for revolving and do not claim that broadly; but

What I do claim as new, and desire to secure by Letters Patent, is

1. In a drilling apparatus, the combination of a spring-actuated contact-block, a rotating base, cl utch-pawls pivoted in said rotatingbase, a tappet-plate attached to the said base,spring actuated cleats for rotating said tappet-plate, and a release-bumper attached to the contactblock by means of rods, substantially as described and for the uses and purposes set forth.

2. In drilling apparatus, the combination with a drill-shaft of a spring-actuated contactblock, a rotating base, a tappet-plate attached to the rotating base, spring-actuated cleats for rotating said tappet-plate, clutch-pawls, pivoted in arevolving base, said clutch-pawls having over their upper ends curved plate metallic springs which prevent the clutchpawls from entirely releasing their hold on the drill-shaft, and a release-bumper connected with the contact-block, substantially as shown and described.

3. In a drilling apparatus the combination with the drill-shaft of a contact-block, a coilactuating spring therefor, two clutch-pawls with curved plate metallic springs on the ends thereof, a rotating base having pivots for the retention of said clutch pawls, a releasebumper with connecting-rods, a tappet-plate with projecting spokes, solidly attached to the rotating base, a driver-head having a circular opening in which the rotating base is rotated, spring-actuated cleats which engage the said projecting spokes on said tappet-plate and cause the tappet-plate and attached parts to revolve during the backward motion in the driver-head, substantially as shown and described.

4. In a drilling apparatus the combination with a drill-shaft, of a coil-actuating spring, a contact-block, two clutch-pawls with curved plate-springs on the upper ends thereof, pivoted in arotating base, atappet-plate attached to the rotating base, spokes on the rim of said tappet-plate, spring-actuated cleats arranged to engage and guide the said spokes, actuating-springs for said cleats, a release-bumper block connected with the contact-blocks by means of rods, a driver-head having a circular opening in it in which the rotating base is allowed to turn, the said driver-head also having suitable connections for pitinen, and guides, arranged to operate in the ends of the driver-head to steady and guide it, two pitman-rods connecting the driver-head with the crank-shaft, a crank-shaft so connected by said pitman-rods with the said driver-head, substantially as shown and described.

5. In a drilling apparatus, the combination with a drill-shaft, of a coil-actuating spring, a contact-block actuated by the said spring, a rotating base fitted to revolve in a driverhead, a driver-head, a tappet-plate securely attached to the rotating base, projecting spokes on said tappet-plate, cleats adapted to engage and move the said spokes, actuating-springs IIS for such cleats, a bumper-block attached to scribed and for the uses and purposes set the contact-block by means of rods passing forth. through the tappet-plate and rotating base, Intestirnony whereof Ihavesignedmyname two clutch-pawls pivotally mounted in the to this specification in the presence oftwo sublactating bcitse, ltwol pitmeln cgnnecting till: scribing witnesses.

criver-hea wit t e cranz-s aft, a cran shaft, casing having a top and furnishing JACOB WILLARD bearings for the crank-shaft, guides attached Witnesses: to the inside of the casing, which engage and t J. E. LITTLE, 1 direct the driver-head, substantially as de- ARA B. PERRYMAN. 

